Audio and audio-video recording on electronic apparatus is now common. Devices ranging from professional video capture equipment, consumer grade camcorders and digital cameras to mobile phones and even simple devices as webcams can be used for electronic acquisition of motion video images. Recording video and the audio associated with video has become a standard feature on many mobile devices and the technical quality of such equipment has rapidly improved. Recording personal experiences using a mobile device is quickly becoming an increasingly important use for mobile devices such as mobile phones and other user equipment. Combining this with the emergence of social media and new ways to efficiently share content underlies the importance of these developments and the new opportunities offered for the electronic device industry.
In such devices, multiple microphones can be used to capture efficiently audio events. However it is difficult to convert the captured signals into a form such that the listener can experience the events as originally recorded. For example it is difficult to reproduce the audio event in a compact coded form as a spatial representation. Therefore often it is not possible to fully sense the directions of the sound sources or the ambience around the listener in a manner similar to the sound environment as recorded.
Multichannel playback systems such as commonly used 5.1 channel reproduction can be used for presenting spatial signals with sound sources in different directions. In other words they can be used to represent the spatial events captured with a multi-microphone system. These multi-microphone or spatial audio capture systems can convert multi-microphone generated audio signals to multi-channel spatial signals.
Similarly spatial sound can be represented with binaural signals. In the reproduction of binaural signals, headphones or headsets are used to output the binaural signals to produce a spatially real audio environment for the listener.